macOS

macOS is an operating system within the Unix family tree that is developed by Apple and is often used for developing Python applications.

macOS is an implementation of the operating systems concept. Learn more in the deployment chapter or view the table of contents for all topics.

Using Python on a Macintosh explains how Python 2.7 is installed by default on Macs. You should start setting up your environment by installing Python 3 and then follow the instructions in the post to get a development environment configured.
Python Development Environment on macOS High Sierra takes the defualt macOS environment and gives you the step to configure everything for Python development.
How to Set Up Your Python Environment is a data science-flavored configuration guide.
How to Use the Command Line for Apple macOS and Linux explains the Terminal. If this guide is useful to you then you should also check out the shells and Bash pages.

How should Python libraries be installed on a server?

Which web server should I use?

What is the Django web framework?